Board & Batten Wood Siding
If you tour around Canada’s stunning East Coast, known for its damp and wind-driven weather, you will regularly spot vintage outbuildings that still retain their original board and batten siding. This vernacular building treatment was the most efficient option in the heyday of the timber-frame barn, whose horizontal framing members were well-suited to vertical siding attachment. With the advent of mass-produced nails and sawmills turning out dimensional lumber, stick-framed buildings evolved as the typical construction method. However, stick-framing is comprised mainly of vertical parts, leaving little in the way of nailing points for vertical siding. Thus, horizontal siding became mainstream and board and batten fell by the wayside, except for mostly post and beam outbuildings.
The increased popularity of rainscreens lends itself well to a revival of board and batten siding. A rainscreen is created when siding is spaced off the building’s sheathing/moisture barrier with furring strips. The airspace that is formed allows any moisture that gets past the siding to dry out before it causes damage. Furring strips are most easily attached horizontally to stick framing, which provides perfect nailing points for vertical siding. It has been argued that rainscreens are more effective with vertical furring strips, since water that infiltrates can drain directly downward. However, siding should be applied so that it fulfills its primary purpose: to shed water. Properly installed, breathable siding coupled with adequate roof overhangs should not allow significant water leakage in the first place.
The bottom layer is pressure-treated to protect from splash back. Spacer boards are visible at lower right.
Optional thicker furring strips at second story/gable ends add interest and efficiency of materials.
Window, door flanges and trim require nailing all the way around an opening.
The simplest window and door trim is made from 2×4" lumber with aluminum drip cap.
Board Placement at Rough Openings
Seams should not be placed at the edge of a window or door. Notice how some boards were spaced further apart to ensure seams were located in the correct position.
The depth of this cut-out is arbitrary depending on board spacing, but is generally at least 2" from either edge of the board.
Schmidt often makes her own cedar drip cap from 2×4" material, but the approach to cutting boards around aluminum cap is the same. Angle the top cut and leave a bit of a gap above the drip cap to encourage water shedding and evaporation.
Finish Before Installation
Now is the best time to apply finish. The boards won’t move around on you, and you are sure to cover the entire front face of every board so if the battens shrink you will still see finished surfaces.
Glue and screw corner boards for added strength. Schmidt prefits, finishes then installs each corner board as a unit.
Note the partial angle cut on the battens under the window. This will drastically reduce the chance the batten soaks up, or misdirects, water.
Why I Love It
As a woodworker, I most enjoy working with materials and finishes that are not harmful to me, my clients or the environment. I also enjoy sourcing local materials. After all, we do not have much opportunity to do that here on the prairies. I love that board and batten can be made to look polished with surface treatments such as rounded edges and sanding, but can also be instantly rustic when constructed with rough sawn lumber and all its lovely machine marks. I love that I can apply this siding as a crew of one, with only a couple of ladders and a hammer. It is also great that the remnants can be disposed of enjoyably, in a backyard bonfire. Given today’s artificial construction materials, board and batten is a rare task that feels like a clean, outdoorsy endeavour. Bring out the noisy compressors and nail guns if you must; I will stick with my 16 oz. straight claw.
Hands down, cedar is the holy grail of wood siding, but the cost can be prohibitive. Of course, here on the dry prairies, it is perfectly sensible to use raw spruce as a siding material, especially in vertical application. Raw woods develop a patina that may be uneven, due to sun exposure, but are wonderfully maintenance-free. In damper climates, spruce is still acceptable when finished with solid colour stain. There are many exterior finish options, but be sure to use a breathable finish. There is an argument to finish both sides of the boards to minimize cupping. As well, wood expands and contracts seasonally and uncoloured stripes may appear as the wood moves; therefore, it is best to apply finish to the boards before the battens are installed.
One-by-eight inch boards are very efficient, as one board can be ripped into three strips of roughly 2.5″ to use as battens. You can vary the board and batten widths, or there are many other variations on this theme. This siding can be done as batten-on-board, as described in this article, board-on-board (for improved water shedding and/or if you do not have access to a table saw) or even board-on-batten.
One-by-four inch spruce is the most efficient and readily available material for strapping. Set up your saw horses and circular saw and fill your pouch with framing nails. Using pressure-treated 1x4s, start at any corner and run a first layer of furring flush with the bottom of the sheathing, using two nails at each and every stud. The entire weight of the siding will hang off these furring strips, so they should be well attached. Split furring strips on a stud where necessary (stagger these splices on subsequent layers) and angle the nails to catch the framing.
Remaining layers of furring are regular 1×4″ spruce. Cut two spacer boards at 21″ for installing subsequent layers of furring. Tack the spacer boards to the siding so that the second layer of furring will be 2′ above the first layer. The spacer boards also allow you to install the furring strips without assistance, as you can prop one end on the spacer board while nailing the other end. Move these spacer boards around and up as you progress. If you wish to break up the wall face (gable end or second story) for interest and/or ease of installation, change to 2×4″ furring strips above the 8′ height. The 8′ layer can be lowered a couple of inches for easier nailing under the eaves, if the roof pitch is steep. On the gable end walls, run furring strips parallel to the roof line and then fill in the horizontals. Run furring to the edge of any rough opening then fill in around the entire opening for flange and trim attachment. Note that if you are using 2×4s for trim, you will need a few pieces of 1×6″ furring for the top and bottom of the window and door openings to accommodate nailing of both the trim and siding.
Trim can be as simple as applying 2×4″ dimensional lumber directly onto window and door flanges (after whatever waterproofing treatment you desire). For windows, start at the bottom and cut a piece of 2×4″ at 1/16″ longer than the window. Rip or plane a 10° angle on the top edge to assist water shedding. Round-over or sand the edges before installing. Attach every foot or so with pairs of fasteners. To get the length of the side pieces, hook your tape onto the top of the window on each side and measure down to the bottom of the lower trim you just installed. Once side pieces are attached, measure and install the top trim. Using roofing nails, install a length of aluminum drip cap along the top. Door casing runs past the bottom in the same manner. Side pieces run past the bottom furring strip about an inch, as will the siding.
As you work, set aside any less knotty boards to be ripped into battens. To allow for expansion and contraction, boards are attached with only one nail in the center of the board at each furring strip. If you use boards wider than 8″, or are worried about cupping, you can drive two nails 3″-4″ apart, rather than one nail in the centre. Boards can be spliced with a mitre if longer lengths are required. If the lumber is quite green, install boards without leaving any space between them, if possible. It is not always possible to achieve perfect spacing, especially on walls with window and door openings. If boards must be spaced out to fill in an area, gaps can be left of up to 3/4″. It is better to space boards out than to rip boards to fit, as this is time-consuming and unnecessary.
Start at the corners. Cut a board to length, which will be an inch or so past the bottom furring, depending on how much clearance there is to the ground. After two corners on a side are installed plumb, run a string line off the bottoms between them to keep a nice line.
The next boards to go on are cut around each side of any openings so that battens do not land at the corner of a window. Cut the board a little long to start. Hold the board against the side of the trim and mark the drip cap angle and bottom edge of the window onto the side of the board. On the sawhorses, use a combination square to transfer these lines onto the face. The width of the cut-out depends on how you will be spacing the boards. The top cut should mirror the angle of the drip cap. Test the fit. The cut-out should butt against the bottom of the window trim, while there should be 1/16″+ of space above the drip cap. If the fit is adequate, mark and cut the board to length off the string line.
Fill in boards between those already installed, cutting the same drip angle over windows and doors. Plumb each board as you install it, especially if there are a lot of bowed boards. This is a great time to apply finish, if that is your plan. Chalk a line for the bottom of the upper layer of boards and install these next.
Count and rip the number of battens required based on the number of seams. Battens can be rounded over for a more refined look and also prefinished. Plumb each batten as you install it and try to center it over the gap. First-level battens are the same length as the boards. Again, mirror the drip cap angle over windows. Corner boards are generally around 4–5″ wide and are glued and screwed. Below the window, cut a bit of an angle on the top edge of the batten so that it does not protrude and catch water. Upper layer battens and corner boards are the final touches.
Celine Schmidt - [email protected]
Celine brings her perspectives of furniture maker, builder and timber framer to projects in Saskatoon, Saskatchewan.